Process for breaking petroleum emulsions



Patented Aug. 11, 1936 UNITED STATES PATENT OFFICE PRooEss Fort BREAKING PETROLEUM EMULSIONS Melvin De Groote, St. Louis, and Bernhard Keiser,

Webster Groves, Mo.,

assignors to Tretolite Company, Webster Groves, Mo., a corporation of Missouri 1 Claim.

This invention relates to the treatment oi emulsions of mineral oil and water, such aspetroleum emulsions, for the purpose of separating the oil from the water, the present application being a division of our co-pending application for Patent Serial No. 760,030, filed December 31, 1934.

Petroleum emulsions are of the water-in-oil type, and comprise fine droplets of naturallyoccurring waters or brines, dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. They are obtained from producing wells and from the, bottom of'oil storage tanks, and 5 are commonly referred to as cut oil, roily oil,

emulsified oil and bottom settlings.

The object of our invention is to provide a novel and inexpensive process for separating emulsions of the character referred to into their component parts of oil and water or brine.

Briefly described, our process consists in subjecting a petroleum emulsion of the water-in-oiltype to the action of a treating agent or demulsifying agent of the kind hereinafter described,

thereby causing the emulsion to break down and separate into its component parts of oil and water or brine, when the emulsion is permitted to remain in a quiescent state after treatment, or is subjected to other equivalent separatory 92 procedures. a

The treating agent or demulsifying agent used in the process which forms the subject-matter of our co-pendi-ng application for patent previously mentioned, consists of an oxy-hendecencic acid material, and particularly a mate--' rial of the kind in which an oxy-hendecenoic acid body has entered into an esteriflcation reaction in the capacity of an alcohol. The most desirable reagents are those obtained by reaction of an hendecenoic acid body and a detergent-forming acid of the kind hereinafter described, or else with a polybasic carboxy acid.

Hendecenoic acid is an unsaturated acid cimilar to certain fatty acids, but apparently not gs occurring naturally in any fat or oil. It is a lower homologue of oleic acid, and is obtained acid is well knownand is described in the pub lication Dictionary of Applied Chemistry, by Thorpe, 1922. In volume 4, pages 630 and 631 of the said publication, the formation of heni5 decenoic acid is indicated as follows:

In producing the treating agent or demulsifying agent, it is not necessary that the hendecenoic acid, which is employed as a raw material, be absolutely pure, but it may be of a technical quality, so as to contain some unconverted castor oil and certain products of decomposition other than hendecenoic acid. It may contain some oenanthol (heptoic aldehyde). This aldehyde can be removed by blowing air or aninert gas through the commercial hendecenoic acid at a relatively low temperature.

As stated in our co-pending application, hendecenoic acid of technical purity may be subjected to oxidation by any of the methods conventionally employed for oxidation of castor oil, and the like. Our preference is to oxidize hendecenoic acid at relatively low temperatures by means of moist air under pressure. We prefer to use a temperature of 125 to 135 C. and to use approximately 45 to '75 lbs. pressure. If desired, hendecenoic acid may be oxidized at a higher temperature by means of air or oxygen at atmospheric pressure.

We have referred to the product obtained by oxidizing hendecenoic acid as oxyhendecenoic acid. The expression oxyhendecenoic acid is intended to refer to the derivatives in which additional oxygen has been introduced into the molecules. For instance, this may be in the manner indicated by the formula cnHzooa. This represents the saturation of the ethylene linkage by means of an atom of oxygen. It is believed that oxidation, especially with moist air, results in the conversion of this added oxygen atom into two hydroxyl radicals, so that ultimately one apparently obtains dihydroxyhendecatoic acid, as indicated by the formula CnHMOI-IMOZ. In other words, the addition product of hendecenoic 40 acid is the substitution product, at least hypothetically, of hendecatoic acid.

In order to summarize what has been said previously, one may consider hendecenoic acid as being "CmHmCOOI-I. The hendecenoic acid residue CmHw may be designated for sake of convenience as T, and thus the acid may be considered as T.COOI-I, and the oxy acid may be considered as Y.T.COOH, wherein Y is at least one oxygen atom, or at least, one hydroxyl radical, CO0 is a conventional carboxyl residue, and T.COO is the hendecenoic acid radical.

Y.T.COOH is: an alcoholic type acid in the same sense that ricinoleic acid is an alcoholic acid. ,Y.T.CO0H may be converted into a salt or ester,

" organic radical, and of course, will be contemv 1 may be esterified with any suitable alcohol, such.

"20. as ethyl alcohol, methyl alcohol, etc., so as to' plated by the described.

' As to reactions of oxy-hendecenoic acid bodies in which the acid bodies act as an acid, reference is made to the following paragraph in our copending application: After producingsuch oxyhendecenoic acid bodies, a's'previously explained, they may be 'used in the acid condition or neutralized with any suitable base-so as to produce an ammonium. salt, a sodium'salt, potassium salt, calcium'salt, magnesium salt, etc.,' or they produce anii e'sterfl suchpoxyhende'cenoic acids 1 maybe combined with basic amines, such as triethanolamine *"Wj e are. lowing manner 7 TI-Iendece'noi'c. acid of technicalfpurityfis 'cau tiouslybxidiz'ed to yield 'dihydroxyhendecatoic iprerneqflfeagentmin r01- acid. Approximately 'l48'lbsfof phthalicifan hydride are mixedflwith"92f 1bs. of glycrol'ja hd heated for;approximatelyT10." to, '15 minutes at 125-150 C.,"until athin, water-white liquid resin 7 intermediate free from any. unreacted-on glycerol has been produced. This f'produet is'character iz 'e'd by: having 'a" free hydroxyl radical available [for 'further' esterificationfi'To this liquid resin intermediate, freejfrom'"unreactecbon glycerol,

1' thereis addedj218lbsI of'dihydroxyhen'decato'ic acid, and the :Inixtureis heated'from l50-2501C.

for 'approximat'elyli) to 30 r'riinutesfafter it is' cooled and isfdiluted to l050%, by weightfof denaturedalcohoh The compound is then ready for use and should. not exhibit" any ifree car- 'boxylic hydrogen. "Should'a small amount of addition of triethanolamine.

*E'sterificzitiqn may take place'jnot only with an acidity bepresent," it may be no tralized by'the alcohol, but with analcohol'acid typerof mai .terial, such'as ricinoleic acidif Oxyhendec'enoic' acid "bodies' may react withjtl'ie hy'dr'oxyl of w an oxy acid; suchas ricinoleic acid, or'the'lik'e, and

the ester 'sop'roduc'ed may be further neutralized, by -the, addition of the usual bases, such asjcau's tie-soda, etcL r v e a, 7 V I iiIt is immaterial" as to the particular method employed to neutralize various dem'ulsifying.

' agentsi 'I'l lefollowing paragraph appears in our ac-pending. applicationmeferred, to above? 7 The usefoi :derhulsifying;agentsconsisting. of various carboxy aci'dsor, compounds having'morej than one 'c arboxyl "group, is well 'known in the treatment or water in-oil emulsions. In the use.

-oi. conventional demulsifying "agents itfis the commoniipractice to use them'not onlyfin the 1 65' form of acids, ]9ut also in the form oflsalts or esters or hal'ff'saltsfor half esters, orlestr salts,

l inlI cas'e ofdibafsicacids. Where such reagents hasten i arb x h rq e and. q c

hydrogen; it"islwell known that onlyfthe sulfonic r rose need-he neutralized, if desired, .The salts generally femployedare the sodium salt;

pfoftassium salt, ammonium salt, calcium, mag "nesium, the triethanolamine' salt, etc. The

formula, Y.T.COOZ, as previously 3 esters may be employed, such as the methyl ester, ethyl ester, propyl ester, butyl ester, amyl ester, hexyl ester, octyl ester, etc. ,Aromatic or cyclic esters may be employed. What has been said, in regard toithe use of conventional demulsifying' agents applies also to: the materials employed as the demulsifying agent of our process.

Conventional demulsifying agents employed in thetreatment of oil field emulsions are used as'such, or after dilution with any suitable solventjsuch as Water, petroleum hydrocarbons,

such as-gasoline, kerosene, stove oil, a coal tar p oduct, suchaS benZene, toluene, xylene, tar acid oil, cresol, anthracene oil, etc. Alcohols, particularly'aliphatic alcohols, such as methyl alcohol, :ethyl alcohol, denaturedalcohol, propyl alcohol,"buty1 alcohol, hexyl alcohol, octyl alcohol,.1etc.,,-may be employed as diluents. Miscellaneous': solvents, such as pine oil, carbon tetrachloride, sulfur dioxide extract obtained in the refining of-petroleum, etc., may be employed as diluents. Similarly, the material- 'or'ma'terials employed-asfthe demulsifying agent of'our process may be admixed With one or more of the solvents customarily used in connection with conventional demulsifying agents. Moreover, said material or materials may'be'used alone or in admixture with other suitable well known classes of demulsifying .agents, such as demulsifying agents of the modified fattyacid type, the petroleum sulfonate'type', the alkylated sulio-aromatic type, etc. I a a T It is-well known that conventional demulsifying agents may be used in a water-solubl'e-form, or in an oil-soluble form, or in a formexhibiting both oil and water-solubility. Sometimes they maybe usedin a form'whieh exhibits relatively limited water-solubility and relatively limited oil-solubility. However, since such reagentsare sometimes used in a'ratio of 'l-'to""l0,000, or 1 to' 20,000,151" 1' to 30,000; such anapparent in-- solubility in oil and water is not significant, because said reagents undoubtedly'hav'e solubility within the concentration employed. This same fact istrue in regard to the materialor materials employed as thedemuls ifying agent of our process.

' In practising our inv'en'tion; a treating agent or demulsifying agent of the kind above-ides'crihed is brought into contact with: or caused to act upon' the emulsion to be treated, in any of the various ways or by any of the various apparatus now generally used to resolve or break petroleum emulsions-with a chemical reagent.

' Having thus described our invention, what we claim 'as new and desire to secure' by Letters Patent is: l V 1 A process for breaking petroleum; emulsions of the water-in-oil type, which consistsin subjecting the emulsion to the-action of ademulsifying agent obtained 'by a' reaction involving oxyhendecenoic a'cidacting as an acid, and said demulsifying agent being characterized by thetype formula Y.T.CO O;Z whereinY isat least oneoxygen atom or at least ohe -hydroxyl radical,.T"is the hendecenoic acid residueCmI-Iim-COO is the conventional-carboxyl'residue, and Z is an acidic hydrogen equivalent,- selected from the class consisting of organic radicals, metallic atoms and amine radicals.

MELVIN 'DEGROOTE.

BERNHARD KEISER. 

